This is going to be harder than I thought

Just got a very disappointing result for the second (and high ranking) of 5 assignments for the OU writing course.  I can't help thinking the standard to be achieved for a good mark is a bit too high for beginners.  Its not very encouraging to just barely pass and receive rather insubstantial comments to go with it.  I'm considering withdrawing from the course; the combination of this disappointment and my struggle with poetry makes me question the value in spending £650 on this course.